The scientific community has been excited for the past decade by the potential of cancer therapy with Monoclonal Antibodies, either alone or as immunoconjugates with drugs, toxins, or radionuclides. In spite of the specific cancer cell targeting and in vitro antibody cytotoxicity for cancer cells, results of clinical trials in cancer patients have been generally disappointing. The goal of this project is to develop a therapeutic approach to metastatic breast carcinoma with combined radioimmunoconjugates and other BRM's, to be studied by quantitative methods and combined in dose levels and sequences that are based on the pharmacokinectic data ad optimal tumor uptake, therapeutic ratio, and tumor response. Using tumor uptake (delivery) of pharmaceutical as the 'gold standard' we will determine the optimal biological dose (OBD) as well as optimal timing of the sequential doses to maximize the tumor dose. The tumor uptake and the effects of radioimmunoconjugate therapy delivered in this manner will be then compared to the tumor uptake and response when further BRM's are added in sequence under the same quantitative scrutiny.